Flame spray gun with improved drive mechanism



Oct. 8, 1968 H. c. THOMPSON FLAME SPRAY GUN WITH IMPROVED DRIVE MECHANISM Filed Jan. 11, 1965 I5 Sheets-Sheet l INVENTOR HENRY c. THOMPSON Oct. 8, 1968 H. c. THOMPSON Y3,404,823

FLAME SPRAY GUN WITH IMPROVED DRIVE MECHANISM Filed Jan. 11,v 1965 A 3 sheets-sheet 2 INVENTOR HEN/y c. THOMPSON BYEMW EMA@ 5f ATTORN YS Oct. 8, 1968 H. c. THOMPSQN 3,404,823

FLAME SPRAY GUN WITH IMPROED DRIVE MECHANISM Filed Jan. ll, 1965 3 Sheets-Sheet 5 INVENTOR HENRJ C'. THOMPSON BY 5P ATTOR E YS United States Patent O 3,404,823 FLAME SPRAY GUN WITH IMPROVED DRIVE MECHANISM Henry C. Thompson, Westbury, N.Y., assignor to Meteo Inc., Westbury, N.Y., a corporation of New Jersey Filed Jan. 11, 1965, Ser. No. 424,750 14 Claims. (Cl. 226-178) This invention relates to a flame spray gun with an improved drive mechanism. The invention more particularly relates to a wire type flame spray gun having an improved governor system for the wire drive.

Wire type flame spray guns are known, commercial items of equipment which, for example, are described in United States Patents 2,381,931, 2,381,932, 2,382,111 all of Aug. 14, 1945, and 2,539,487 of Ian. 30, 1951.

In wire type flame spray guns a wire (the term wire being used generically to designate a wire or rod) is fed through the gun where the end of the wire is continuously melted or heat-softened and atomized by a blast of gas into a spray which is projected away from the gun, as for example against a surface to be coated. The wires most commonly used are metal wires, and for this reason flame spray guns are often referred to as metal spray guns or metallizing guns. The materials sprayed by these guns,

however, are not limited to metal, and any heat-fusible material in wire form may be sprayed, including refractory oxides.

In most wire type flame spray guns the wire is fed through the gun by being passed in contact with a rotating roller, wheel, cylinder, or the like, which is referred to as a wire feed roll and which is motor driven. Generally, the wire is passed through the nip of a pair of wire feed rolls 'which are roughened, milled, or the like, to provide the necessary gripping contact with the wire. The wire feed roll or rolls is generally driven by a suitable motor, such as a gas turbine or electric motor. To maintain the desired spray under given conditions and when spraying a given wire, the speed of the wire feed must be precisely controlled. Furthermore, in order to spray different materials, the speed control must be adjustable. For example, lower melting point wires must generally be sprayed at a higher rate of speed than higher melting point wires. The speed control may be effected by a suitable speed governor, as for example, a power absorption governor of the type described in US. Patents 2,381,931, 2,381,932, and 2,382,111, though in connection with electrical drives, it is known to utilize electrical or electronic governors, as for example, where the back developed by the motor is utilized to regulate the power supplied to the motor, as for example through an electronic valve.

When spraying, the force required to feed the wire through the gun, i.e. the pull on the wire, may vary, depending upon the position of the gun; the feed device for the wire coil; whether kinks and bends in the wire are encountered; `and the changes in the required lfeeding force may occur rather abruptly.

With the known speed governors, and particularly the power-absorption type speed governors, an actual change in the wire feed speed must occur before the governor is actuated to allow the supplying of additional power when the same is necessary, i.e. upon the encountering of an increased resistance in the wire feed. Thus, for example, as the wire is fed through the gun at a given speed as controlled by the governor, when increased resistance in the feed, as for example by a kink in the wire, is encountered, the feed must actually slow down before the governor is actuated to, for example, decrease the amount of power absorbed and allow a greater percentage of the power to be fed to the wire feed. There may also be a certain degree of hunting until the governor will readjust itself to the desired speed.

These changes in the feed speed as caused by variations in the resistance to feed by the wire, may cause variations in the uniformity of the spray, or even interruptions or failures.

It is an object of this invention to provide a wire type flame spray gun having a governor system for its drive which does not have the above-mentioned disadvantages.

It is a further object of this invention to provide a wire type flame spray gun having a speed-governed drive which can vary the driving force supplied to the wire, as required, without an undesirable speed change.

A still further object of this invention is to provide a wire type flame spray gun having a power absorption type speed governor which can respond to changes in load without an undesirable speed chan-ge.

These and still further objects will become apparent from the following description read in conjunction with the drawings in which:

FIG. 1 is a side elevation, partially in section, of an embodiment of a wire type flame spray gun in accordance with the invention;

FIG. 2 is a plan view, partially in section, of the embodiment `shown in FIG. 1;

FIG. 3 is a front elevation of the embodiment shown in FIG. l;

FIG. 4 is a diagrammatic exploded perspective view showing the wire feed drive and governor of the embodiment in FIG. 1;

FIG. 5 is a diagrammatic exploded perspective view of elements of the speed governor of the embodiment of FIG. l;

FIG. 6 is a diagrammatic perspective view of a further embodiment of a torque-sensing element which may be be used in accordance with the invention; and

FIG. 7 is a diagrammatic perspective view of a further embodiment of a torque-sensing element which may be used in accordance with the invention.

The flame spray gun to which the invention is directed is of the type having a wire feed roll for feeding Wire through the gun, and a speed-governed drive for the wire feed roll. The improved construction in accordance with the invention comprises torque-sensing means which is responsive to the drive torque of the feed roll. The torque-sensing means is operationally connected to the drive for varying the power output of the drive transmitted to the feed rolls in accordance with variations of the torque of the feed roll.

Referring to the embodiment shown in FIGS. 1-5 of the drawing, the wire type flame spray gun is basically of the known form and construction, having the turbine and feed housing 1, the handle 2, and the gas head 3. The gas head, which is of the conventional and wellknown construction, as for example described in detail in United States Patent 2,539,487 of Ian. 30, 1951, basically consists of a nozzle arrangement which is positioned in the gas head and extends into the blast gas or air cap 4. The burner nozzle head has a central wire feed passage, through which the heat-fusible wire being sprayed is fed, which passage is surrounded by a ring of burner jets which are fed a combustible gas mixture, as for example a mixture of oxygen and acetylene, oxygen and propane, or the like. The gases are fed as individual components through individual supply lines and the plug valves designated at 5, and are mixed in the gas head in mixing passages positioned in a syphon plug.

A blast gas, such as air, is also fed through the arrangement 5 and passes around the burner nozzle through the air cap 4. The combustible gases are ignited as a flame as they emerge from the burner nozzle, and heat-soften or melt the tip of the wire being fed through the central passage of the burner nozzle. The stream of blast gas iiowing through the air cap impinges on the heat-softened tip of the wire and continuously atomizes the same, propelling the atomized particles as a spray away from the gun.

The wire, designated as 6, is fed into the rear of the gun through the guide bushing 7, passing through the nip of the wire feed rolls 8 and 9, and through a wire feed passage extending through the gas head, and through the burner nozzle as described above.

The wire feed roll 9 is mounted in the housing 10 which is hinged at 11. By adjustment of the thumb screw 12, with its spring 13, the position of feed roll 9 may be adjusted with respect to that of 8, i.e. the gap between the rollers may be varied, and the pressure exerted on a wire passing therebetween controlled so as to allow adequate gripping for reliable wire feed. The wire rolls 8 and 9 have conventional milled surfaces where they engage the wire to prevent slipping. A gear 14 is mounted alongside the feed roll 8 for rotation therewith, and a gear 15 is mounted alongside the feed roll 9 for rotation therewith. The teeth of the gear 14 engage those of the gear 15 so that the roll 9 will rotate with the roll 8 and there will be a positive transmission of drive from the roll 8 to the roll 9. The feed roll 8 is driven by a gas turbine through a gear train, including a worm and a worm gear, and the speed of rotation is controlled by a centrifugal brake-type power-absorption governor.

The feed roll 8 is mounted for rotation on the shaft 16, on which is also mounted the worm gear 17 (FIGS. 2 and 4). The worm gear 17 meshes with a worm 18, mounted for rotation on the shaft 19 with the worm gear 20. The worm gear 20 meshes with the worm 21, which is connected to the turbine shaft 22, on which is mounted the turbine rotor 23. Also rotatably connected to the turbine shaft 22, but axially slidable therealong, is the brake disc 24. As shown in FIG. 5, a fly weight arrangement, consisting of the spring 25 and fly weights 26, is connected to the turbine rotor by means of the rivets 27. The fly weights 26 will be thrown out against the spring force by centrifugal action on rotation of the turbine rotor and moving the spring clip 28 connected to the brake disc, thus forcing the brake disc to slide axially along the shaft 22 against the force of the coil spring 29 so that the brake disc will contact the iixed braking surface in the form of the annular brake shoe 30 which is slidably mounted adjacent the control ring 31, which may be rotated by hand-screwing the brake shoe by means of the screw threads 32, in and out of the turbine housing, so as to adjust the position of the brake shoe 30 with respect to the brake disc 24. Brake disc 24 is caused to rotate with rotor 23 by the ears on spring clip 28, which engage weights 26.

The turbine rotor is driven by a portion of the blast gas stream passing through the turbine nozzle 33 and impinging on the blades of the turbine rotor, causing the same to rotate.

In operation, wire is fed into the gun and the gripping force of the feed rolls 8 and 9 are adjusted by means of the thumb screw 12. Gas is passed through the gun and the gun lit in the conventional manner, and the turbine is driven by the blast gas passing through the turbine nozzle 33. Rotation of the turbine rotates the worm 21 which drives the worm gear 20, which in turn rotates the worm 18 which drives the worm gear 17, driving the wire feed roller 8, which through the gear train 14, 15 also drives the wire feed roll 9.

As the speed of the turbine increases, tiy weights 26 are thrown outwardly against the force of spring 25 and push the spring clip 28, sliding the brake disc 24 toward the brake shoe 30 against the pressure of the spring 29 which is held in the bushing 34 which rests against the end bearing 35 of the turbine shaft. As the brake disc 24 contacts the brake shoe 30, a braking action occurs, absorbing power from the turbine, so that the turbine will run at a speed determined by the position of the brake shoe 30. Any speed increase beyond this point simply results in greater centrifugal action on the fly weights 26, forcing the brake disc 24 in firmer engagement with the brake shoe 30, thereby increasing the amount of power absorbed and decreasing the speed; conversely, any decrease in speed causes a reduction in pressure, with which the brake disc 24 presses against the brake shoe 30 and finally allows the brake disc, by action of the spring 29, to move away from the brake shoe 30, thus decreasing the power absorbed and allowing speed increase to the desired set value, The preset speed is increased by screwing the control ring 31 to move the brake shoe 30 outwardly, and decreased by screwing the same to move the brake shoe 30 inwardly.

The construction and operation of the flame spray gun as described to this point is conventional and well known, and is as described in the aforesaid United States patents.

With this structure, if a sudden increase in the pull of the wire by the feed rolls 8 and 9 occurs, as for example may be occasioned by a kink or bend in the wire, the increased pull will tend to slow the turbine down. Only after the turbine has slowed down will the force between thebrake disc 24 and the brake shoe 30 be lessened by the decrease in the centrifugal force on the fly weights 26, so that amount of power absorbed by the brake is decreased and the corresponding amount of power transmitted to the feed rolls increased, so Yas to compensate for this increased drag allowing the turbine to speed up again, at which point it must hunt and find its preset speed.

Conversely, if the pull on the wire is decreased, as for example by the operators moving the gun rearwardly or the like, the turbine will increase in speed and the adjustment will only occur as a result of this speed increase. Thus, with the speed governor an undesirable initial speed change of the wire feed is a necessary prerequisite for a regulation of the governor to compensate for changes in pull on the wire.

In accordance with the invention the turbine shaft 22 is mounted in the turbine housing for limited axial movement.

The turbine end of the turbine shaft is mounted in the ball bearing 35, which is seated in a bearing bushing 36 in the end cover 36a. The bearing 35 has free end play and is provided with the linger spring 37 to resiliently take up this free end play. The bearing, the finger spring, and the bushing 34 are secured to the turbine shaft 22 by means of the nut 38.

The opposite end of the turbine shaft, i.e. the worm end, rotates in the ball bearing 39, also connected thereto by means of a nut 40. The outer race of the ball bearing 39 is axially extended to form a cylindrical socket into which a cylindrical bushing 41 tits. Secured on the end of the cylindrical bushing 41 is a disc spring 42. The bearing 39 slidably fits in a socket 43 in the end of the turbine housing, and the disc spring 42 rests on a ringshaped spring stop 44.

As the turbine 23 rotates in the direction of its arrow as shown, the worm 21 drives the worm gear 20 in the direction of the arrow shown on the worm gear 20. In effecting this drive, there is naturally an axial component of force on the worm 21 in the direction toward the disc spring 42. This force is opposed by the disc spring 42. This force is solely a function of the torque on the worm 21 and thus the torque on the feed rolls 8 and 9. With an increase in torque on the feed rolls 8 and 9, for example as caused by a greater drag on the wire 6, there with which the brake disc 24 presses against the brake shoe 30, thus reducing the power absorbed by the governor. Thus, as may be seen, an increase in torque on the wire feed rolls, as caused by a greater drag on the wire, automatically increases the power output of the drive transmitted to the wire feed rolls and thus automatically compensates for the greater drag without speed variation.

The limited axial movement of the shaft 22 against the spring 42 thus constitutes torque-sensing means which is responsive to the drive torque of the feed rolls. This torque-sensing means is operationally connected to the drive by means of connection of the brake disc 24, so that the power output of the drive transmitted to the feed rolls is varied in accordance with variations of the torque of the feed rolls.

The finger spring 37 does not exert any appreciable force but mainly serves to preload the shaft 22 against 'the Ispring stop 44 and to take up the end play of the bearing 35 as the shaft 22 is moved axially against the disc spring 42 and when the disc spring 42 axially moves lthe shaft 22 in the opposite direction upon decrease in torque.

Upon a sudden decrease in torque, the spring 42 will force the shaft 22 in the opposite direction as the force component of the worm 21 against the spring 42 is reduced, thus forcing the brake disc 24 in firmer engagement with the brake shoe, increasing the power absorbed to compensate for the decrease in torque without va. corresponding speed change.

The combination of the speed governor with the .torque governor, in accordance with the invention, allows 1an ideal control of the wire feed and allows the speed control to be maintained irrespective of changes in pull on the wire. The combination allows the drive shaft r.p.m. to be controlled within very narrow speed range limits over wide wire load variations. The effect of the torque sensitive governor can be so controlled that as the output load increases, the shaft output r.p.m. either decreases, remains constant, or increases as desired. Further, in practice it has been found that the speed governor plus the torque governor can provide a controlled sp'eed range, which is wider than when just the speed governor is used.

As a practical example, the wire speed regulation ability under varying wire loads, of a llame spray gun of conventional construction solely containing the speed governor, was compared to the same gun as modified to include the torque governor in `accordance. with the invention. For this purpose a llame spray gun manufactured by Metco, Inc., Westbury, Long Island, and sold under the name of Metco Type 4E Gun was used as the conventional gun. This gun has vthe construction shown in FIGS. 1-5 of the drawing, except that the turbine shaft 22 is axially secured without end play. This gun was compared with the same model gun modified in accordance with the invention as lshown in FIGS. 1-5. In each of the tests, the guns were adjusted to feed wire at a given speed with no load on the wire; then various loads of 10, 20, 30 and 50 pounds were applied to the wire, and the resulting wire speed noted. This new speed was divided by the initial speed and multiplied by 100 to give a Value ter-med percent regulation. The results are noted in the tables below.

In Table 1 the no-load speed was 1.6 ft. per minute; in Table 2, 2.7; and in Table 3, 5.4. In the tables the first column indicates the load added to the wire in the form of a dead weight added to the wire in pounds, the second column indicates the regulation of the conventional gun, and the third column the regulation in accordance with the invention. The percentages above 100% indicate a slight increase in speed as the load is applied.

TAB LE 1 Percent regulation Wire pull, lbs.

Conventlonal gun Invention 1 Turbine stalled.

TAB LE 2 Percent regulation Wire pull, lbs.

Conventional gun Invention TAB LE 3 Percent regulation Wire pull, lbs

Conventional gun Invention The invention is not limited to the particular type of flame spray gun and drive, as shown, but is broadly applicable to llame spraying guns in general having a speed governor drive for the wire. This drive may, for example, be electric or any other known or conventional drive.

While the torque-sensing means may be preferably used in combination with a power absorption type of speed governor, in order to vary the amount of power absorbed by the governor in accordance with torque, the same may be used in connection with other types of governors. Thus, the actuation force of the torque-sensing means, such as the -movement of the shaft, may be used directly to act and vary other types of governors, or directly supply an increase or decrease in power to the drive. For example, movement of the shaft constituting the torque-sensing means may be utilized to increase or decrease an electrical resistance, as for example through a rheostat or pressure variable resistance, in order to control the electric circuit which varies the power. This actuation may also be used to control an electronic device which varies the power in accordance with the movement or pressure thereof.

In place of the torque-sensing means, as shown, any other known or conventional torque-sensing means may be utilized. The torque-sensing means may, for example, constitute any element or component in the drive train which is provided with mating inclined surfaces havin-g an angle greater than the friction angle, and in which at least one of these elements is movable in relation to the other against a resilient force. The sliding component between these surfaces is, of course, dependent on the overall torque transmitted through the system and thus the degree of movement or the pressure between the surfaces is a measure of the torque which may be used for the control as for example to vary the amount of power absorbed by the power absorption speed governor.

Referring, for example, to the embodiment shown in FIG. 6, the shaft 45 has the coupling 46 connected thereto, which is provided with the serrated teeth formed by the inclined surfaces 47.

This coupling mates with a similar element 48 having the teeth with the inclined surfaces 49, and is connected for rotation to the shaft 50. If the shaft 45 is yaxially movable a limited amount in the direction of the arrow, and is urged axially toward the shaft 50, the inclined surfaces 47 will mate with the inclined surfaces 49, so that rotary power is transmitted between the shafts 45 and 50. As the degree of torque between these shafts increases, so does the axial component, tending to push the shafts apart as the inclined surfaces 47 and 49 tend to slide along each other. This axial movement of the shaft 45 away from the shaft 50 against the resilient pressure increases as the torque increases, so that the axial movement of the shaft 45 will vary in accordance with the torque. This may be used for varying the power transmitted by the drive to the wire in accordance with the invention. Thus, for example, the coupling may be positioned in the shaft 22 between the brake disc 24 and bearing 35; and the worm and gear 20 and 21 may be replaced by an ordinary gear drive and the bearing 35 axially fixed.

In the embodiment shown in FIG. 7 the beveled gears 51 and 52 are provided having mating teeth with inclined surfaces, the inclination of which from the base is less than the friction angle. As the gear 51 drives the gear 52, there is an axial component of force on each of these gears, tending to move the same apart, with a force dependent on the torque therebetween. With limited movement of one of these gears against a resilient spring force, this movement may be utilized to vary the power transmitted by the drive to the wire. Thus, in the embodiment of FIG. 4 the worm 21 may be replaced by the gear 52, and a gear corresponding to the gear 51 provided in the gear train meshing therewith and .operationally connected to the drive roll 8. In the embodiments shown in FIGS. 6 and 7, the torque-sensing elements may be considered as gears in the gear train of the drive, spatially movable with respect to each other, with variations of the torque transmitted through the drive just as the worm gear 21 in FIG. 4 may be considered as spatially movable with respect to the gear 20.

While the invention has been described in detail with reference to certain specific embodiments, various changes and modifications which fall within the spirit of the invention and scope of the appended claims will become apparent to the skilled artisan. The invention is therefore only intended to be limited by the appended claims or their equivalents wherein I have endeavored to claim all in herent novelty.

I claim:

1. In a wire type flame spray gun having a wire feed roll for feeding wire through the gun and a speed-governed drive for said wire feed roll, the improvement which comprises torque-sensing means directly responsive to the drive torque of said feed roll, without speed change, said torque-sensing means being operationally connected to said drive for varying the power output of said drive transmitted to said feed roll in accordance with variation-s of the torque of said roll whereby the power output is increased with an increase of the torque and decreased with a decrease of the torque.

2. In a wire type flame spray gun having a wire feed roll for feeding wire through the gun, a drive for said wire feed roll and a power absorption speed governor for said drive, the improvement which comprises torque-sensing means directly responsive to the drive torque of said feed roll, without speed change, said torque-sensing means being operationally connected to said governor to vary the power absorbed thereby inversely with the variations of the torque of said roll.

3. Improvement according to claim 2 in which said drive includes a gear train and in which said torque-sensing means includes a gear of said gear train spatially displaceable out of the plane of its rotation with variations of the torque transmitted therethrough.

4. Improvement according to claim 3 in which said spatially displaceable gear is an axially movable worm.

5. In a wire type ame spray gun having a wire -feed roll for feeding wire throu-gh the gun, a speed-governed drive motor and a drive train including a worm and meshed worm -gear connecting said feed roll and drive motor, the improvement which comprises said worm gear being mounted for limited axial movement, and means responsive to axial movement f said worm for varying the power transmitted by said motor to said feed roll without speed change.

6. Improvement according to claim 5 including a power absorption speed governor for said motor and means actuated by axial movement of said wonm for varying the power absorbed by said governor.

7. Improvement according to claim 6 in 'which said power absorption governor includes a speed actuated brake, and in which said means actuated by axial movement of said worm is rneans for varying the braking power of said brake.

8. lIn a wire type fiame spray gun having a wire feed roll for feeding wire through the gun, a drive motor, a drive train, including a worm with a rotating worm shaft drive, connecting the drive motor and feed roll, a power absorbing speed governor including a movable 'brake ele ment connected to said shaft and a fixed brake element, and means for moving said movable brake element into braking engagement 'with said fixed brake element, with a force increasing with increasing spee-d of rotation of said shaft, the improvement which comprises said shaft being lmounted for limited axial movement, said worm being meshed in driving engagement with a worm gear of said train so that the same has an axial force component when driven by said motor in a direction to move said movable brake elernent away from said fixed brake element, and spring means urging said shaft in the opposite direction.

9. Improvement according to claim 8 in which said movable brake element comprises a brake disc mounted for rotation with said shaft and for limited sliding movement axially along said shaft, y weights mounted for rotation with said shaft and operationally connected to said disc to slide the same along said shaft toward said fixed brake element when said fiy weights are centrifugally moved by rotation of said shaft.

10. Improvement according to claim 9 in which said spring means comprises a disc spring positioned at the end of said shaft.

11. Improvement according to claim 8 in which said motor comprises a gas turbine having a rotor mounted on said shaft.

12. In a wire type flame spray gun having a pair of wire feed rolls for feeding wire through the gun, a gas turbine having a rotor with a rotor shaft, a worm on said rotor shaft, a worm gear meshing with said worm and connected through a `gear train to said wire feed polls, a brake disc mounted for rotation with said rotor shaft and for limited sliding movement axially along said shaft, y weights mounted for rotation with said rotor shaft and operationally connected to said brake disc, to slide the same along said shaft toward a fixed brake shoe when said fly weights are centrifugally moved by rotation of said rotor shaft, the improvement which comprises said rotor shaft being mounted for limited axial movement, said worm being connected to said worm gear so that the drive transmitted by said rotor produces an axial component in a direction moving said brake disc away from said fixed brake shoe and spring means urging the rotor shaft axially in the opposite direction.

13. Improvement according to claim 12 in which said spring means comprises a disc spring positioned on the end of said shaft remote from said brake disc.

14. Improvement according to claim 13 including a finger spring -for taking up end play on the opposite end of said rotor shaft.

References Cited UNITED STATES PATENTS 2,120,896 6/1938 Koeppen et al.

2,781,616 2/1957 Estabrook.

3,049,098 8/1962 Inoue 173-12 X 3,174,606 3/1965 Hornschuch et al. 173-12 X 3,185,366 5/1965 Charlop 226-176 ROBERT B. REEVES, Primary Examiner.

v N. L. STACK, Assistant Examiner. 

1. IN A WIRE TYPE FLAME SPRAY GUN HAVING A WIRE FEED ROLL FOR FEEDING WIRE THROUGH THE GUN AND A SPEED-GOVERNED DRIVE FOR SAID WIRE FEED ROLL, THE IMPROVEMENT WHICH COMPRISES TORQUE-SENSING MEANS DIRECTLY RESPONSIVE TO THE DRIVE TORQUE OF SAID FEED ROLL, WITHOUT SPEED CHANGE, SAID TORQUE-SENSING MEANS BEING OPERATIONALLY CONNECTED TO SAID DRIVE FOR VARYING THE POWER OUTPUT OF SAID DRIVE TRANSMITTED TO SAID FEED ROLL IN ACCORDANCE WITH VARIATIONS OF THE TORQUE OF SAID ROLL WHEREBY THE POWER OUTPUT IS INCREASED WITH AN INCREASE OF THE TORQUE AND DECREASED WITH A DECREASE OF THE TORQUE. 